Add C++ functions to FootTrajectoryGeneration for more efficient frame conversion + Control from yaml + Again a few changes for RPY to quaternion conversion

Merge from Devel Croco 14/07/2021

See merge request !2

Choice of MPC with integer + Foot trajectory generator after MPC in case MPC optimizes footsteps + Adapt MPC Crocoddyl with footsteps optimization to the new architecture

Switch all solo12 loading to SoloLoader + architecture to run scenarios from another script + Clean test_4 + New EulerToRotation function

Remove osqp files that were included in the repository since they were conflicting with the standard osqp install

Change control architecture to work in horizontal frame with reference quantities instead of relying more on estimated quantities

Add vertical offset in MPC to take into account position of CoM under position of the middle of the base